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EntelliGuard* L

Overload Protection LT-C and LTD

Overload (LT-C) Protection
The EntelliGuard* GT-L Electronic Trip has an SET UP LONG TIME
extremely accurate and easy to set overload or
Long Time (LT-C) Protection . It is designed to pick METER pickup
up overloads that exceed 112% of the set value 0.5
(1)
within two hours with a tolerance of 10% . STATUS BAND
C5
EVENTS Ir = 500A
The device has 15 setpoints distributed over a
setting range of 0.4 to 1 times the chosen breaker
rating (In)
EntelliGuard GT-L Electronic Trip Unit
The LT-C type is designed to be used in 10000 - Time Current Curve
association with down- and upstream circuit 2h LT- Protection Device Overcurrent protection
breakers and has a so called I t shape producing C bands
2
a curve form similar to standard industrial
thermal magnetic protection devices.
The Time-Current protection curve depicted here 1000
is drawn in cold state A cooling function in the
device corrects for the heating of the connected
lines and equipment.

In order to allow an accurate adjustment to the Intro
thermal properties of the protected equipment 100
and to finely match the curve with those of
Upstream & Downstream devices 22 time bands A
are available.

The table indicates the minimum delay time and
maximum total interruption times for 3 frequently 10 B
used reference points on the curve of each band.
The graph portrays the LT behaviour for the time-
current bands C-4,C- 8, C-13 & C-22. C
Tripping Time In Seconds (s) 1 D

0,1
0 , 1 0 1 0 , 0 0 1 0 0 , 0 0 E
x Breaker Rating In 7,2 x
X
]

Overload Tripping times at indicated overload levels per selected LTD band, in Seconds
x Ir Cmin C-2 C-3 C-4 C-5 C-6 C-7 C-8 C-9 C-10 C-11 C-12 C-13 C-14 C-15 C-16 C-17 C-18 C-19 C-20 C-21 Cmax
Max. 7,8 23,4 46,7 62,3 93,4 125 156 187 218 249 280 311 374 436 498 560 623 685 747 810 872 934
1.5
Min. 4,0 12,0 24,0 32,0 48,0 64,1 80,1 96,1 112 128 144 160 192 224 256 288 320 352 384 416 448 480
Max. 1,3 3,86 7,73 10,3 15,5 20,6 25,8 30,9 36,1 41,2 46,4 51,5 61,8 72,1 82,4 92,7 103 113 124 134 144 155
3
Min. 0,80 2,41 4,82 6,43 9,64 12,9 16,1 19,3 22,5 25,7 28,9 32,1 38,6 45,0 51,4 57,8 64,3 70,7 77,1 83,6 90,0 96,4
Max. 0,21 0,62 1,24 1,66 2,49 3,32 4,15 4,98 5,81 6,64 7,47 8,30 9,96 11,6 13,3 14,9 16,6 18,3 19,9 21,6 23,2 24,9
7.2
Min. 0,13 0,40 0,81 1,07 1,61 2,15 2,69 3,22 3,76 4,30 4,83 5,37 6,45 7,52 8,60 9,67 10,7 11,8 12,9 14,0 15,0 16,1
Motor Protection Class to IEC 947-4 10b 10 20 30 40
(1) Meeting the requirements of IEC 90647-2 and IEC 90647-4

B.3